Corrupted partitions can be caused by a lot of things -- bad drive, bad SATA cable, bad SATA controller, overclocking, flaky power, and bad RAM are all potential culprits. Have you seen any other signs of system instability, or are you only having issues with this one data drive?

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I am having difficulty getting diagnostic utility from the vendor. The problem is with a machine of my relatives where I am visiting. I decided to replace it with a new one of a different brand. Thanks to all responded.

I replaced the hard drive as previously posted but the exact same problem symptoms remained. The symptoms include frequent CHKDSK running, data partition becoming "RAW", OS becoming no boot, system freezing, etc.

I ran Memtest and it reported errors. I ran Memtest for one module at a time and found one of the pair did not generate error.

I tried one which did not report error and found the system was stable.

I got a new pair of RAM module of a different brand, ran Memtest and found that this pair also generated error. I went ahead and tried this new pair to find that the system is just as stable as when one of the old pair was used as above. The following is a screen shot of the Memtest. The error happened always at the Test #6 with new pair or old pair. It appears that culprit of this problem is bad RAM. I wonder why the new RAM pair does not cause instability even the Memtest reports errors.

It's going to be about the access pattern (i.e. combination of reads and writes) that triggers the error in the memory. The original sticks probably would fail under conditions that you are hitting commonly when running normally, whilst the new sticks may only fail under a particular access pattern that you are not happening to hit.

notfred wrote:It's going to be about the access pattern (i.e. combination of reads and writes) that triggers the error in the memory. The original sticks probably would fail under conditions that you are hitting commonly when running normally, whilst the new sticks may only fail under a particular access pattern that you are not happening to hit.

Does this mean that why no problem with the new sticks was that the machine was not used exactly the same way as when the old sticks were used?

True that the way I used the machine was not exactly the same but generally the same way because I was testing the machine which I just built. Also it is generally unlikely that the two different brands of new RAMs have the same type of defect as reported by the diagnostic utility. With the old sticks the problem symptoms happened consistently, while with the new sticks the problem never happened for two consecutive days.

Last edited by churin on Wed Jun 26, 2013 6:22 pm, edited 1 time in total.

notfred wrote:It's going to be about the access pattern (i.e. combination of reads and writes) that triggers the error in the memory. The original sticks probably would fail under conditions that you are hitting commonly when running normally, whilst the new sticks may only fail under a particular access pattern that you are not happening to hit.

Does this mean that why no problem with the new sticks was that the machine was not used exactly the same way as when the old sticks were used?

No, I mean that whilst the new pair fail, they only fail under slightly more stress than the new pair. How you use your machine is between the two points so in general use you see failures with the old but not with the new. Memtest is stressing the memory to the limit so it finds all the failures.

churin wrote:Also it is generally unlikely that the two different brands of new RAMs have the same type of defect as reported by the diagnostic utility.

It could also be a problem in the memory controller (i.e. CPU), memory sockets or motherboard traces.

notfred wrote:No, I mean that whilst the new pair fail, they only fail under slightly more stress than the new pair. How you use your machine is between the two points so in general use you see failures with the old but not with the new. Memtest is stressing the memory to the limit so it finds all the failures.

You appear to indicate that the extent of the defect of the new sticks is smaller so that I will eventually see the same problem. Is this correct?

churin wrote:

notfred wrote:Also it is generally unlikely that the two different brands of new RAMs have the same type of defect as reported by the diagnostic utility.

It could also be a problem in the memory controller (i.e. CPU), memory sockets or motherboard traces.

I would think these hardware conditions can be considered the same since I only replaced the old sticks with the new sticks and everything else was unchanged.

notfred wrote:No, I mean that whilst the new pair fail, they only fail under slightly more stress than the new pair. How you use your machine is between the two points so in general use you see failures with the old but not with the new. Memtest is stressing the memory to the limit so it finds all the failures.

You appear to indicate that the extent of the defect of the new sticks is smaller so that I will eventually see the same problem. Is this correct?

Yes, you may be lucky and never see the issue again or it may crop up at some later point in time.

churin wrote:

notfred wrote:It could also be a problem in the memory controller (i.e. CPU), memory sockets or motherboard traces.

I would think these hardware conditions can be considered the same since I only replaced the old sticks with the new sticks and everything else was unchanged.

True, but it could be a the new sticks are more tolerant of something being just slightly off in those components e.g. poor connection in the memory socket and new sticks have slightly better but still not good enough.

On the whole I think I would just RMA the new RAM sticks and try again to get a set that passes memtest without errors.